package com.book.dao;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.book.entity.BookClass;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;

@Mapper
public interface BookClassDao extends BaseMapper<BookClass> {
    @Select("SELECT class_name FROM book_class WHERE id = #{id} and del_flag=0")
    String selectClassNameById(@Param("id") int id);//书的id

}